The answer to 'how much is smoke detector upgrade' is that the cost can vary significantly depending on several factors. Upgrading smoke detectors typically ranges from a simple DIY project costing $20-$50 per unit to a professional installation that may cost $100-$300 per detector.
The main factors that influence the cost of a smoke detector upgrade include the number of detectors needed, the type of detectors (basic, smart, or interconnected), whether you're doing it yourself or hiring an electrician, and any necessary wiring or electrical work required. Getting local quotes from licensed electricians is essential to determine the precise cost for your specific home.